存在xml:base时Firefox无法识别SVG本地IRI

在SVG元素上指定了xml:base属性时，Mozilla Firefox无法理解SVG文档中xlink:href属性上的本地IRI引用

相同的SVG文档在Google Chrome中显示良好

尝试删除到xml:base属性，Firefox将通过其本地ID查找元素：

<?xml version="1.0" encoding="utf-8"?>
<svg version="1.1"
    xml:base="http://samplehost.com" 
    xmlns:ev="http://www.w3.org/2001/xml-events" 
    xmlns:svg="http://www.w3.org/2000/svg" 
    xmlns:xlink="http://www.w3.org/1999/xlink" 
    xmlns="http://www.w3.org/2000/svg" 

    viewBox="0 0 236.00000 148.00000" 
    height="148.00000" 
    width="236.00000"
>

<def>
    <symbol id="86310c35-a7e1-47c0-90c8-b6f912d2cead" viewBox="0 0 113.39 70.87" enable-background="new 0 0 113.39 70.87">
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<use xlink:href="#86310c35-a7e1-47c0-90c8-b6f912d2cead" x="0" y="0"/>
</svg>

重点是示例SVG文档中的符号元素没有在Firefox中呈现。这正是我的观点-符号元素由本地IRI引用（它不是相对引用，也不是绝对引用，它是仅由片段引用的本地资源）。From SVG支持两种类型的IRI引用：本地IRI引用，其中IRI引用不包含or，因此只包含片段标识符（即#或#xpointer（id））非本地IRI引用，其中IRI引用确实包含或引发错误：